This proposal describes a population-based cohort study aimed at determining the relationship between retinal vascular characteristics (such as generalized and focal retinal arteriolar narrowing, venular dilation, and arterio-venous (AN) nicking) and the incidence and progression of diabetic retinopathy, ischemic heart disease and stroke mortality, and the incidence of lower extremity amputation and diabetic nephropathy in people with Type 2 diabetes. For this epidemiologic study, subjects include all persons who: (1) were 30 years of age or older at the time of their diagnosis; (2) had received primary medical care in an 11-county area of south central Wisconsin; and (3) were identified from doctors' records in 1979-80. Standardized protocols for examinations and interviews have been employed during the baseline, and 4- and 10-year follow-up examinations. Refusal rates have been low. [unreadable] [unreadable] Color stereoscopic fundus photographs of the Diabetic Retinopathy Study 7 standard fields were taken of each eye at the baseline and follow-up examinations. Retinopathy severity was determined by grading these photographs using the Aiflie House classification system. In addition, standardized protocols were used to measure blood pressure, height and weight; a blood specimen was drawn to determine glycosylated hemoglobin and blood glucose; and a urine specimen for analysis for protein. A medical history included items on smoking status, hypertension, heart disease, stroke, lower extremity amputation, medications, etc. Death certificate information was obtained. [unreadable] [unreadable] We plan to scan the fundus photographs taken at the baseline examination and the 4-year follow-up and do computer-assisted grading for retinal vessel diameter and light box grading for focal arteriolar narrowing and AN nicking in this cohort. This will permit us to examine the associations of focal and generalized retinal arteriolar narrowing and AN nicking with the incidence and progression of retinopathy, ischemic heart disease and stroke mortality, and the incidence of lower extremity amputation and diabetic nephropathy controlling for other risk factors. Findings regarding these associations will be useful for understanding the pathogenesis of these complications, for developing preventive strategies for them, and for other research investigating these relationships in people with [unreadable] Type 2 diabetes. [unreadable] [unreadable] [unreadable] [unreadable]